A risk score for ventricular arrhythmia in mitral valve prolapse

Abstract Background Prior studies have identified that complex and frequent ventricular ectopy (cfVE) predicts sudden death in patients with mitral valve prolapse (MVP). Purpose To develop a risk stratification score which predicts rates of cfVE in patients with MVP based on clinical, ECG and echocardiographic features. Methods Data was collected on 637 patients aged 18–90 years with MVP at our institution between 2016-2019. Complex and frequent ventricular ectopy was defined as the presence of > 1% premature ventricular contraction (PVC) burden or non-sustained ventricular tachycardia on Holter monitoring or > 1 PVC on 12-lead ECG. Univariate analysis was performed to identify independent predictors of cfVE. Factors found to be statistically significant on univariate analysis were then evaluated using multivariate logistic regression. Variables analyzed included age greater than 65, moderate or greater mitral regurgitation, female gender, African American race, atrial fibrillation, coronary artery disease, congestive heart failure, inferior or lateral T wave inversion, bileaflet (vs. unileaflet) prolapse, myxomatous mitral valve morphology, mitral annular dysjunction, left ventricular ejection fraction less than 40%, left ventricular hypertrophy, diabetes, and hypertension. Risk points were attributed to multivariate predictors of cfVE using their odds ratios. Predicted probability of cfVE, derived by logistic regression, was used to categorize scores into low, moderate, and high risk. Rates of cfVE were compared between risk groups using Pearson’s Chi-squared test. All-cause mortality was compared between risk score groups with Kaplan-Meier analysis. Results Complex and frequent ventricular ectopy was present in 182 (28.6%) patients. Multivariate predictors of cfVE were mitral annular disjunction (MAD, OR 3.2, 95% CI 1.9-5.4), bileaflet (vs. unileaflet) prolapse (OR 2.1, 95% CI 1.4-3.3), congestive heart failure (OR 2.2 95% CI 1.3-3.7) and inferior or lateral T wave inversion (TWI, OR 2.1, 95% CI 1.3-3.2). Risk points of 1.5 for MAD and 1 for bileaflet prolapse, CHF and TWI were totaled to group patients into low (score 0, n=274, 43.0%), moderate (score 1-2, n=276 ,43.3%) and high (score 2.5-4.5, n=87,13.7%) risk groups. Rates of cfVE were 11.7% for low, 35.5% for moderate and 59.8% for high-risk groups (p<0.0001). On Kaplan Meier analysis, risk group significantly correlated with mortality (p<0.0008). Conclusion In patients with MVP this risk stratification tool, using the presence of mitral annular disjunction, bileaflet prolapse, history of congestive heart failure and T-wave inversion, represents a viable method of predicting risk of cfVE, which correlates with all-cause mortality.Univariate and multivariate analysisKaplan-Meier Curve